[PATCH] uml: allow building as 32-bit binary on 64bit host

This patch makes the command:

make ARCH=um SUBARCH=i386

work on x86_64 hosts (with support for building 32-bit binaries).  This is
especially needed since 64-bit UMLs don't support 32-bit emulation for guest
binaries, currently.  This has been tested in all possible cases and works.

Only exception is that I've built but not tested a 64-bit binary, because I
hadn't a 64-bit filesystem available.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 4 insertions, 7 deletions

diff --git a/arch/um/Makefile b/arch/um/Makefile
index 6a7a9f43cde..eb4ac403bd9 100644
--- a/arch/um/Makefile
+++ b/arch/um/Makefile
@@ -51,11 +51,6 @@ MRPROPER_DIRS	+= $(ARCH_DIR)/include2
 endif
 SYS_DIR         := $(ARCH_DIR)/include/sysdep-$(SUBARCH)
 
-include $(srctree)/$(ARCH_DIR)/Makefile-$(SUBARCH)
-
-core-y += $(SUBARCH_CORE)
-libs-y += $(SUBARCH_LIBS)
-
 # -Dvmap=kernel_vmap affects everything, and prevents anything from
 # referencing the libpcap.o symbol so named.
 
@@ -64,7 +59,7 @@ CFLAGS += $(CFLAGS-y) -D__arch_um__ -DSUBARCH=\"$(SUBARCH)\" \
 
 USER_CFLAGS := $(patsubst -I%,,$(CFLAGS))
 USER_CFLAGS := $(patsubst -D__KERNEL__,,$(USER_CFLAGS)) $(ARCH_INCLUDE) \
-        $(MODE_INCLUDE) $(ARCH_USER_CFLAGS)
+        $(MODE_INCLUDE)
 
 # -Derrno=kernel_errno - This turns all kernel references to errno into
 # kernel_errno to separate them from the libc errno.  This allows -fno-common
@@ -74,6 +69,8 @@ USER_CFLAGS := $(patsubst -D__KERNEL__,,$(USER_CFLAGS)) $(ARCH_INCLUDE) \
 CFLAGS += -Derrno=kernel_errno -Dsigprocmask=kernel_sigprocmask
 CFLAGS += $(call cc-option,-fno-unit-at-a-time,)
 
+include $(srctree)/$(ARCH_DIR)/Makefile-$(SUBARCH)
+
 #This will adjust *FLAGS accordingly to the platform.
 include $(srctree)/$(ARCH_DIR)/Makefile-os-$(OS)
 
@@ -132,7 +129,7 @@ CPPFLAGS_vmlinux.lds = -U$(SUBARCH) \
 #The wrappers will select whether using "malloc" or the kernel allocator.
 LINK_WRAPS = -Wl,--wrap,malloc -Wl,--wrap,free -Wl,--wrap,calloc
 
-CFLAGS_vmlinux = $(LINK-y) $(LINK_WRAPS)
+CFLAGS_vmlinux := $(LINK-y) $(LINK_WRAPS)
 define cmd_vmlinux__
         $(CC) $(CFLAGS_vmlinux) -o $@ \
         -Wl,-T,$(vmlinux-lds) $(vmlinux-init) \